1. Field of the Invention
This invention pertains to break-away tensile links which are used to retain one body to another until a predetermined separation force level is reached. More particularly, this invention pertains to such break-away links which possess high resistance to flexural fatique damage coupled with predictable tensile parting force.
2. Description of the Prior Art.
When certain types of thrust propelled missiles, such as rocket powered missiles, are ignited and launched, some releasable means for retaining the missile to its launching apparatus must be used to prevent the missile from leaving the launching apparatus before the rocket motor reaches its full thrust level. Unless some retaining means is used, the missile may launch at a low thrust level and become unstable, resulting in uncontrollable flight.
Past attempts to solve this problem have utilized a frangible tensile link between the rocket and the launching apparatus. This link restrains the rocket until rocket thrust exceeds the strength of the tensile link, at which time the link parts, releasing the rocket. One problem encountered with such a tensile release link is that if the link has been subjected to bending stresses over a period of time, structural fatique in the link will take place. A fatigue weakened link may part prematurely with resultant adverse effects upon the rocket trajectory.
Other attempts to solve this problem utilize complicated mechanisms which clamp the rocket to the launching apparatus until the moment of release. At the proper time the clamping mechanisms spring away from the rocket, releasing it. These mechanisms are generally heavy, and, because of their added complexity, they increase the expense as well as the chance of launch failure.